1. Field of the Invention
The present invention pertains, in general, to brace bars attached to an inner surface of a sound board of a guitar to prevent the sound board from being deformed and, more particularly, to a brace bar attached to an inner surface of a sound board of a guitar, which has a modified shape to improve the flexibility of the sound board while maintaining the strength of the sound board, thus improving the resonance of the sound board and reducing a weight of the sound board.
2. Description of the Related Art
Generally, as shown in FIGS. 1 and 2, a guitar includes a body 1 having a sound board 1a attached to an upper part thereof, a block 2 made of wood attached to an inner surface of the body 1 and having a groove 2a to receive a neck 3, the neck 3 being connected to the block 2 in such a way that a lug 3a of a heel 3b of the neck 3 is inserted into the groove 2a of the block 2, a fingerboard 4 attached to an upper surface of the neck 3, a bridge 5 attached to an upper surface of the sound board 1a of the body 1, a brace bar 6 attached to a lower surface of the sound board 1a, a head 7 integrated with an end of the neck 3 which is not connected to the body 1, strings 8 connected between the bridge 5 and the head 7, and a fingerboard adjusting rod 9 longitudinally installed on an upper, central surface of the neck 3 to adjust a state of an even surface of the fingerboard 4.
The guitar is provided with a resonant sound board 1a to resonate for a relatively long time and to make peculiar sounds.
To prevent the sound board 1a from being distorted while it is used for a long term, various kinds of brace bars 16, 16′, 16a, 16b, 16a′, 16b′ are attached to an inner surface of the sound board 1a as shown in FIGS. 3 and 4. The stronger the brace bar attached to the sound board 1a is, the longer a life span of the guitar is. On the other hand, the flexible brace bar contributes to improving resonance of the sound board 1a to allow the guitar to resonate for a relatively long time.
If the brace bar is not strong, the sound bar 1a bends over time. Thus, the life span of the guitar is shortened because the sound bar 1a does not fulfill its own function. On the other hand, if the brace bar is too strong, the resonance of the sound board 1a is poor even though the sound board 1a is not distorted, thus the guitar makes a poor sound for a short time.
Accordingly, it is preferable that the brace bar has flexibility as well as strength. Furthermore, a shape and the number of the brace bars, and an attachment structure of the brace bar to the sound board 1a, are important factors affecting the performance and durability of the guitar.
Referring to FIGS. 3 and 4, there are illustrated a plurality of brace bars attached to an inner surface of a sound board of a conventional guitar. At this time, shapes and the number of the brace bars, and the attachment structure of the brace bars to the sound board of FIG. 3, are similar to those of FIG. 4. In other words, two pairs of first and second main brace bars 16, 16′ are attached to the inner surface of the sound board in the shape of an ‘X’, and first and second auxiliary brace bars 16a, 16b, 16a′, 16b′ are attached to the inner surface of the sound board as a way to be positioned around the main brace bars. As described above, FIG. 3 is similar to FIG. 4 in views of the shapes and the number of the brace bars, and the attachment structure of the brace bars to the sound board. However, FIG. 3 is different from FIG. 4 in terms of several facts. In detail, the first main and first auxiliary brace bars 16, 16a of FIG. 3 have recessed parts formed on middle portions (a) thereof. At this time, each of the recessed parts forms a bow with its center being bent downward. On the other hand, the second main and second auxiliary brace bars 16′, 16a′ of FIG. 4 have not the recessed parts, and each has a cross-section with a profile of which a side extends vertically upward to a position of a predetermined height, thus forming a lower base part, and extends upward while being bent toward the center of each brace bar to form a parabolic upper part (b), as shown in FIG. 5.
That is to say, in FIG. 3, the first main and first auxiliary brace bars 16, 16a have longer heights than widths to allow the sound board 1a of FIG. 3 to have the strength, and have the bow-shaped recessed parts formed on the middle portions (a) thereof to allow the sound board of FIG. 3 to have increased flexibility. Furthermore, the second main and second auxiliary brace bars 16′, 16a′ of FIG. 4 each has the cross-section with the profile of which the side extends vertically upward to the position of the predetermined height, thus forming the lower base part, and extends upward while being curved toward the center of each brace bar to form the parabolic upper part (b), as shown in FIG. 5, thereby their sectional areas are reduced to allow the sound board 1a of FIG. 4 to have the flexibility to improve the resonance of the sound board 1a and to make a middle- and a low-pitched sound for a relatively long time.
Therefore, the present invention provides a brace bar attached to an inner surface of a sound board of a guitar, which has a modified shape to improve the flexibility of the sound board while maintaining the strength of the sound board.